Aircraft engines are typically enclosed within nacelles having translating thrust reverser sleeves which translate aft relative to the nacelle in order to expose a plurality of thrust-reversing cascade vanes to air flowing through the nacelle. When air flowing through the nacelle contacts the exposed thrust reverser cascade vanes, the air flow is directed in an outward and forward direction, reversing the thrust of the aircraft engine.
Some aircraft nacelles have a variable area fan nozzle (VAFN) configuration, with actuatable VAFN structures that slide, pivot, or otherwise open to increase an area of an aft opening or openings through which air may exit the nacelle. These actuatable VAFN structures are usually part of the translating thrust reverser sleeves of the nacelle.
Thrust reverser actuators for the translating thrust reverser sleeves are typically fixed to a torque box or some other fixed component of the nacelle. VAFN actuators for the actuatable VAFN structures may also be fixed to the torque box, but this requires the VAFN actuators to span a majority of a length of the translating thrust reverser sleeve and a telescoping portion of the VAFN actuators must be long enough to accommodate for the aftward translation of the translating thrust reverser sleeve. This configuration undesirably increases the weight of the VAFN actuators.
In other nacelle arrangements, the VAFN actuators are fixed to the translating thrust reverser sleeve, reducing the length and weight of the VAFN actuators. However, transmitting power to these VAFN actuators remains problematic because of the translation of the translating thrust reverser sleeve. Some configurations may use hydraulic fluid hoses, electrical wiring, or pneumatic hoses capable of accommodating translation of the translating thrust reverser sleeve. However, this presents potential maintenance problems, such as chafed hoses or wiring harnesses or premature hose failures due to repeated flexing.
Some configurations use telescoping mechanical interfaces to provide drive power to the VAFN actuators regardless of the position of the translating thrust reverser sleeve. Once again, there is a weight penalty for such a configuration. Additionally, the contact points between sliding components require maintenance and are subject to contact wear that could potentially lead to part failure.
Therefore, there is a need for an improved system and method for actuating VAFN panels that overcomes the limitations of the prior art.